With respect to Karl's first point, I think Karl is likely to be right. Large multinational corporations are likely to be bidders for new gTLD slots/strings. Certainly as the price of slots comes down, this will be inevitable.With respect to Karl's second point about the cost of operating a TLD, I defer to Karl's superior knowledge. His estimate (even if low by a factor of 10 or 100) suggests that 1000 is far too low as a cap for the ultimate level of TLD demand.Karl's third point (about private TLDs) is absolutely right And as Karl points out, that is the implication of the move to sTLDs.Lawrence Solum

If a registry requires servers across the world, and you take the current registries as the minimum acceptable level of technical ability, then I sincerely doubt that you, Karl, would spend the money for the infrastructure, much less the maintenance.

Your argument presumes that you can run a registry with a single server in your basement. You cannot.